According to the Hacker's Guide for VFP 7 (hope it's ok to quote it here)

nFirstDayofWeek
 Omitted
 Use Sunday as the first day. This is for compatibility with older versions of FoxPro.

>Sergey and Yuri
>

>? DOW(DATE(), SET("FDOW"))
>

>works perfect
>But I read the help. I don't find DOW() function is not affected by SET FDOW
>This is in my help
>

>Returns a numeric day-of-the-week value from a Date or DateTime expression.
>
>DOW(dExpression | tExpression [, nFirstDayOfWeek])
>
>Parameters
>dExpression
>Specifies the Date expression from which DOW( ) returns the day number.
>
>tExpression
>Specifies the DateTime expression from which DOW( ) returns the day number.
>
>nFirstDayOfWeek
>Specifies the first day of the week. nFirstDayOfWeek may be one of the following values.
>
>nFirstDayOfWeek  Description
>0
> DOW( ) uses whatever day is currently selected in the Week Starts On list box, which appears on the Regional Tab in the Options dialog box.
>
>1 Sunday. This is the default when nFirstDayOfWeek is omitted, and is the first day of the week used in earlier FoxPro versions.
>2 Monday
>3 Tuesday
>4 Wednesday
>5 Thursday
>6 Friday
>7 Saturday
>

>Yes [, nFirstDayOfWeek] is parameter but why I need to use this parameter while i have SET FDOW TO? or this is dummy SET ??? unusable may be
>
>>According to help, the DOW() function is not affected by SET FDOW. The following should work for you

>>? DOW(DATE(), SET("FDOW"))
>>

>>
>>>I read thread#1090152 and I try this code
>>>

>>>*** today is Wednesday
>>>clear
>>>SET FDOW TO
>>>? DOW(DATE()) &&& result is 4  = true
>>>SET FDOW TO 2 &&& Monday is the first day
>>>? DOW(DATE()) &&& result is again 4. Why ? Today is Wednesday must by 3
>>>

>>>What do I wrong?
>>>TIA